Nitric oxide manufacturing methods

Nitric acid is a colourless liquid at room temperature and atmospheric pressure. It is soluble in water in all proportions and there is a release of heat of solution upon dilution. This solubility has tended to shape the process methods for commercial nitric acid manufacture. It is a strong acid that almost completely ionizes when in dilute solution. It is also a powerful oxidizing agent with the ability to passivate some metals such as iron and aluminium. A compilation of many of the physical and chemical properties of nitric acid is presented in Table A.1 of Appendix A. Arguably the most important physical property of nitric acid is its azeotropic point, this influences the techniques associated with strong acid production. The constant-boiling mixture occurs at 121.9°C, for a concentration of 68.4%(wt) acid at atmospheric pressure. 

No atoms are lost in the cleavage reaction so that cheap cyclohexene 6 is used to make adipic acid 7 for nylon manufacture. Any of the oxidative cleavage methods from the last chapter could be used Vogel1 has a recipe using concentrated nitric acid on cyclohexanol 8 that presumably goes by dehydration to the alkene 6 followed by oxidation, and other methods are probably used industrially. 

CCls CHO. A colourless oily liquid with a pungent odour b.p. 98°C. Manut actured by the action of chlorine on ethanol it is also made by the chlorination of ethanal. When allowed to stand, it changes slowly to a white solid. Addition compounds are formed with water see chloral hydrate), ammonia, sodium hydrogen sulphite, alcohols, and some amines and amides. Oxidized by nitric acid to tri-chloroethanoic acid. Decomposed by alkalis to chloroform and a methanoate a convenient method of obtaining pure CHCI3. It is used for the manufacture of DDT. It is also used as a hypnotic. 

Nickel sulfate also is made by the reaction of black nickel oxide and hot dilute sulfuric acid, or of dilute sulfuric acid and nickel carbonate. The reaction of nickel oxide and sulfuric acid has been studied and a reaction induction temperature of 49°C deterrnined (39). High purity nickel sulfate is made from the reaction of nickel carbonyl, sulfur dioxide, and oxygen in the gas phase at 100°C (40). Another method for the continuous manufacture of nickel sulfate is the gas-phase reaction of nickel carbonyl and nitric acid, recovering the soHd product in sulfuric acid, and continuously removing the soHd nickel sulfate from the acid mixture (41). In this last method, nickel carbonyl and sulfuric acid are fed into a closed-loop reactor. Nickel sulfate and carbon monoxide are produced the CO is thus recycled to form nickel carbonyl. 

The oxidation of carbohydrates is the oldest method for oxahc acid manufacture. The reaction was discovered by Scheele in 1776, but was not successfully developed as a commercial process until the second quarter of the twentieth century. Technical advances in the manufacture of nitric acid, particularly in the recovery of nitrogen oxides in a form suitable for recycle, enabled its successful development. Thus 150 t of oxahc acid per month was produced from sugar by I. G. Earben (Germany) by the end of World War II. 

Manufacture. Historically, ammonium nitrate was manufactured by a double decomposition method using sodium nitrate and either ammonium sulfate or ammonium chloride. Modem commercial processes, however, rely almost exclusively on the neutralization of nitric acid (qv), produced from ammonia through catalyzed oxidation, with ammonia. Manufacturers commonly use onsite ammonia although some ammonium nitrate is made from purchased ammonia. SoHd product used as fertilizer has been the predominant form produced. However, sale of ammonium nitrate as a component in urea—ammonium nitrate Hquid fertilizer has grown to where about half the ammonium nitrate produced is actually marketed as a solution. 

Eng 20, 470-477 (1919) (Description of ammonia oxidation process beginning with Kuhl-mann s method of 1839 and ending with the cyanamide process at Muscle Shoals) 7) C.L. Parsons, 1EC 11,541 (1919) (Oxidation of ammonia to nitric acid as well as the prepn of nitric acid from Chile saltpeter) 8) F.C. Zeis-berg, ChemMetEng 24, 443-45 (1921) (Manuf of nitric acid from Chilean saltpeter brief description) 9) G.B. Taylor, IEC 26,1217-19 (1922) (Some economic aspects of ammonia oxidation) 10) Ministry of Munitions, Manufacture of Nitric Acid from Nitre and Sulfuric Acid , London (1922) (Book No 7 of Technical Records of Explosives Supply, 1915—1919)... 

Adipic acid is of considerable importance since it is a precursor to nylon and polyester, which are extensively used in many products. Between two and three million tonnes are produced worldwide each year. Currently, its main method of manufacture is a costly, multistep process involving concentrated nitric acid. Nitrous oxide is produced as a by-product in such quantities that they measurably contribute to global warming and ozone depletion [24], A cleaner alternative to this process is clearly highly desirable. 

Commercial lead arsenate usually consists mainly of the monohydrogen arsenate, but may also contain the normal arsenate. It is in great demand as an insecticide (see p. 301). Many methods of manufacture are described in the patent literature,14 some of the more recent being as follows (1) Metallic lead and arsenious oxide are added to a concentrated solution of arsenic acid containing nitric acid 15 lead arsenate is precipitated, the concentration of the arsenic acid remaining constant. At intervals the precipitate is removed and the arsenic acid solution again treated. (2) A solution of a soluble arsenate is treated... 

Nitration offers a method of making unreactive paraffins into reactive substances without cracking. Because nitric acid and nitrogen oxides are strong oxidizing agents, oxidation always accompanies nitration. Aromatic nitration reactions have been important particularly for the manufacture of explosives. Nitrobenzene is probably the most important nitration product. 

Preparation from a- trinitrotoluene. In 1893 a patent was granted to the Chemische Fabrik Griesheim [47a] for the manufacture of sym-trinitrobenzene from trinitrotoluene. The method was based on the fact observed by Tiemann [48] Mid by Claus and Becker [49], that trinitrotoluene can be oxidized with nitric acid to trinitrobenzoic acid, the latter being readily decarboxylated to form sym-trinitrobenzene ... 

The method of manufacture of nitroform from acetylene found as early as 1900 by Baschieri (Voi. I, p. 587) was described by Orton and McKie [141]. It became possible to convert one of the carbons of acetylene to nitroform through a mercury catalysed oxidation-nitration process with nitric acid. Nitroform is an intermediate product of nitration and yields tetranitromethane under the action of excess nitric acid (Vol. I, p. S94). The method was developed during World War II by Schultheiss I42] and Schimmelschmidt 143 on a large laboratory scale with the atm of producing tetranitromethane. l ater the industrial scale method for the manufacture of nitroform was created by Wctter-holm [I44 (and is described below). 

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